SSPTRS(3F)SSPTRS(3F)NAME
SSPTRS - solve a system of linear equations A*X = B with a real symmetric
matrix A stored in packed format using the factorization A = U*D*U**T or
A = L*D*L**T computed by SSPTRF
SYNOPSIS
SUBROUTINE SSPTRS( UPLO, N, NRHS, AP, IPIV, B, LDB, INFO )
CHARACTER UPLO
INTEGER INFO, LDB, N, NRHS
INTEGER IPIV( * )
REAL AP( * ), B( LDB, * )
PURPOSE
SSPTRS solves a system of linear equations A*X = B with a real symmetric
matrix A stored in packed format using the factorization A = U*D*U**T or
A = L*D*L**T computed by SSPTRF.
ARGUMENTS
UPLO (input) CHARACTER*1
Specifies whether the details of the factorization are stored as
an upper or lower triangular matrix. = 'U': Upper triangular,
form is A = U*D*U**T;
= 'L': Lower triangular, form is A = L*D*L**T.
N (input) INTEGER
The order of the matrix A. N >= 0.
NRHS (input) INTEGER
The number of right hand sides, i.e., the number of columns of
the matrix B. NRHS >= 0.
AP (input) REAL array, dimension (N*(N+1)/2)
The block diagonal matrix D and the multipliers used to obtain
the factor U or L as computed by SSPTRF, stored as a packed
triangular matrix.
IPIV (input) INTEGER array, dimension (N)
Details of the interchanges and the block structure of D as
determined by SSPTRF.
B (input/output) REAL array, dimension (LDB,NRHS)
On entry, the right hand side matrix B. On exit, the solution
matrix X.
LDB (input) INTEGER
The leading dimension of the array B. LDB >= max(1,N).
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SSPTRS(3F)SSPTRS(3F)
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
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